Bis (2, 3-hydroxy-naphthoyl-maminophenyl) urea



Patented Dec. 20, 1938 UNITED STATES BIS (2,3-HYDROXY-NAPHTHOYL-M-AMINOPHENYL) UREA Samuel Cofiey, Manchester, and John Edgar Schofield,Huddersfield, England, assignors to Imperial Chemical IndustriesLimited, a corporation of Great Britain 7 No Drawing. Originalapplication March 26,

1932, Serial No. 601,454, now Patent No.

2,093,265, dated September 14, 1937. Divided and thisapplication-November 11, 1936, Serial No; 110,276. In Great BritainMarch 31, 1931 1 Claim.

I This invention relates to novel N,N'-diaryl ureas and a process .forthe production thereof, this application being a division of ourcopending application Serial No. 601,454, filed March 26,

, 1932, now Patent No. 2,093,265, dated September l As is well known,some N,N'-diarylureas are not readily obtained when the correspondingaryll amines are treated with phosgene according to a carbonylderivative by these means.

the general methods hitherto known. Parafnitraniline, for example, doesnot readily give Aniline itself, when treated with phosgene, gives onlyhalf its equivalent of diphenylurea, the remainder of the aniline beingconverted into aniline hydrochloride.

' It is an object of the present invention to provide a new and improvedprocess for the manuf acture of N,N"-diarylureas. A further object isthe provision of a process adapted to the production in a technicallysatisfactory way of N ,N'-

diarylureas from arylamines insoluble or sparing- 1y soluble in water,or devoid of solubilizinggroups. A still further and more specificobject is the production of novel 'ureas fromcompounds of the generalformula RNH2, wherein R is the residue of a compound adapted to be usedas coupling component for azo dyestuffs. Further Objects are theproduction of new chemical compounds and in general to advance the art.Other objects will appear hereinafter.

'These objects are accomplished according to the invention wherebyN,N'-diarylureas are obtained by treating a primary arylamine withphosgene in the presence of a tertiary base. This is preferably effectedby passing gaseous phosgene into the primary arylamine dissolved in ormixed with the tertiary base. A liquid which is indifferent or does notaffect the reaction unfavorably may be advantageously employed in anauxiliary capacity as a solvent, diluent, or suspension medium.

Theinvention will be further illustrated, but is not limited, by thefollowing examples in which the parts are by weight:

Example I below 40 C. The mixture is then heated to 90 C.

for 4 hours, cooled and filtered, andthe precipitate well washed withwater and dried. The

(Cl. 260-553) T bis(2,3-hydroxynaphthoyl-3-aminophenyl) urea obtainedmelts at 275-282 C., and after solution in caustic soda andreprecipitation, at 286289 C. The product is represented by the formula:

2 Example II Fifty-five parts of 1 m-aminophenyl-S-methyl- 5-pyrazolonehydrochloride containing 68.9% by weight of1-m-amino-phenyl-3-methyl-5-pyrazolone (M. W. 189) are agitated with 260parts of toluene and 45 parts of dimethyl-am'line and phosgene (12.5parts) is passed in slowly at 15-30 C. over a period of two hours. Themixture is heated to 90 C. for two hours, cooled and the solid filteredoff and washed with Water containing hydrochloric acid. The solid ispurified by solution in an excess of dilute aqueous sodium carbonate,filtration and reprecipitation with acid. After drying there is obtainedabout 35 parts of the urea having a melting point of 236- 237 C. Theurea is represented by the formula:

HzC-OO =N I NH CH: 2

In the production of diarylureas in accordance with the presentinvention, the amine reacted upon with phosgene may be any primaryarylamine. The hydrogen atoms in the ring nucleus of the arylamine mayor may not be replaced by substituents such as, for example, halogen,nitro, alkyl, alkoxy, substituted amino derivatives (e. g., aryl oralkylacyl-amino), isocyclic and heterocyclic radicals. Mention may bemade of the application of the process to the following specificcompounds: paranitraniline, l-m-aminophenyl- 3-methyl-5-pyrazoloneortho-phenetidine, 2 ,3 hydroxynaphthoyl-mamino'anilide5-chlorol-nitro-o-anisidine, 4 nitro 2,5 dimethoxyaniline CHaO-ortho-anisidine, 5 -nitro-o anisidine, benzylamine, ortho toluidine,meta-toluidine, alpha and beta naphthylamine and the xylidines.

The tertiary base may be any aliphatic and/or aryl basic tertiary amine.The amount thereof employed should preferably be at least sufficient totake up the hydrogen chloride liberated during the formation of theurea. As examples of tertiary bases may be mentioned dimethylaniline,triethanolamine, diethylaniline, die'thylamino ethyl alcohol,trimethylene diamine, tripropylamine, methyl diethanol amine,tribenzylamine, nicotine N CH /N.CHa a Hg /CC\ CH2 CH=CH OH2-CH2quinoline, and pyridine.

While it may notbe necessary in every case to employ a solvent,suspension. agent, or diluent in the reaction, this is generallydesirable to render the reaction mixture more fluid, therebyfacilitating stirring and increasing the smoothness of the reaction. Thekind of solventor suspension agent employed is subject to considerablevariation depending largely upon the nature of the primary and tertiaryamines employed. Generally speaking, we prefer to employ organicsolvents. Such solvents are particularly advantageous Where the aminesare not Water-soluble. Especially desirable results have been obtainedwith benzene, toluene, and ethylene dichloride as solvents.

The temperature at which the operation is performed is preferably thatof the room, but a higher temperature may be necessary or desirable toaccelerate the reaction.

The novel products of this invention are valuable in the chemicalindustry, more particularly for the production of azo dyes by couplingwith diazo compounds in the same manner used to convert the2,3-hydroXy-naphthoyl derivatives of U. .8. Patent 1,987,669 and thediaryl ureas of U. S. Patent 656,646 into azo dyestuffs.

As many apparent and widely different embodiments of this invention maybe made without departing from the spirit thereof, it is to beunderstood that we do not limit ourselves to the foregoing examples ordescription except as indicated in the following claim.

We claim:

The compound, bis(2,3-hydroxy-naphthoyl-maminophenyl) urea correspondingto the following formula SAMUEL COFFEY. JOHN EDGAR SCHOFIELD.

